The men preyed on the families of youngsters to gain access to them and, in one case, groomed a mother and father before their baby was born. Members travelled hundreds of miles to carry out sickening attacks together or used internet streaming to provide real-time encouragement and directions to those abusing victims.
The seven — aged between 31 and 51 and including three convicted sex offenders — were convicted of 29 child sex abuse offences.
They are John Denham, 50, from Wiltshire; Matthew Stansfield, 35, from Hampshire; Adam Toms, 33, from Somerset; Christopher Knight, 35, from Manchester; Robin Hollyson, 31, from Bedfordshire; David Harsley, 51, from Yorkshire; and Matthew Lisk, 33, from Sussex.
Passing sentence at Bristol Crown Court, Judge Julian Lambert said: “In the worst nightmare, from the very deepest recesses of the mind, at the darkest hour of the night, few can have imagined the terrifying depravity which you men admit.
“What you contemplated and what you did involved the most horrific abuse of a baby and very young children.
“Your thoughts and deeds are beyond human instinct and reason, and are evil beyond rational understanding.”
Hollyson received a 24-year prison sentence plus an extension of eight years on licence while Toms was jailed for 12 years plus an extension of four years on licence.
Knight was jailed for 18 years plus an extension of six years on licence and Stansfield received a 10-year prison sentence plus an extension of four years on licence. Denham was jailed for eight years plus an extension of four years on licence.
Lisk was jailed for four years plus an extension of three years on licence and Harsley was jailed for two years They were all placed on the sex offenders’ register for life, except for Harsley whose length is still to be determined by the judge.
Known victims of the men include one baby, aged between three and seven months at the time of the abuse, a four-year-old boy and a boy aged between four and five.